/*
 * Copyright (c) 2011 Imre Fazekas.
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * Neither the name of the Brillien nor the names of its
 * terms and concepts may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

package com.vii.brillien.services.components.util;

import com.vii.brillien.core.component.SuperPresence;
import com.vii.brillien.core.component.spi.AbstractState;
import com.vii.brillien.kernel.BrillienException;
import com.vii.brillien.kernel.annotations.PresenceService;
import com.vii.brillien.kernel.annotations.lifecycle.Resident;
import com.vii.brillien.kernel.axiom.component.State;

/**
 * MessageQueue implementation in Brillien. The entity changes its state in every incoming message
 * inducing a notification to all presence subscribed to this type's state change events
 */
@PresenceService
@Resident
public class MessageQueue<R> extends SuperPresence<R> {

    /**
     * DeliveringState instance
     */
    protected DeliveringState   deliverState;

    /**
     * A special state changing after each incoming message
     */
    protected class DeliveringState extends AbstractState {

        public DeliveringState() {
        }

        public DeliveringState(String name, boolean init, boolean error, boolean exit) {
            super(name, init, error, exit);
        }

        @Override
        public boolean isError() {
            return false;
        }

        @Override
        public boolean isExit() {
            return false;
        }

        @Override
        public boolean equals(AbstractState a) {
            return false;
        }
    }

    @Override
    protected State getDefaultState(){
        return deliverState;
    }

    protected void buildStateStructure(){
        states.clear();
        states.add( deliverState = new DeliveringState( "ServeAndDeliver...", false, false, false ) );
    }

    @Override
    public Object processMessage(String message, Object... parameters) throws BrillienException {
        changeState( deliverState, deliverState );
        return super.processMessage( message, parameters );
    }

}

